Plastic industry is known as a dynamic industry in producing of new materials. Thermoplastic and thermoset resins are widely used by plastic industry and many researches are performed to improve the properties and performance of resin by adding various reinforcements and fillers. High performance of composite materials is caused that researchers pay attention to replace the conductive materials with conductive polymer composites.
Warlimont, et al. studied on manufacturing of lead-acid battery grids by using a multilayer structure. They increased corrosion resistance of grids and decrease the weight of the battery. Warlimont et al. proposed a grid manufactured by copper, lead and tin for lead-acid battery and improved the mechanical, electrical and corrosion resistance behavior of the material. Hill, et al. obtained a higher voltage by using a ceramic material as a battery grid.
In recent years, many researches are performed in manufacturing of batteries by plastic grids instead of lead grids. According to available research, plastics in the best conditions have 0.001 conductivity of lead. In addition, carbon poly-acetylene grids due to instability of poly-acetylene in air and light make some problems. Recent researches on replacement of lead alloy grid with high conductive porous material show that using porous graphite in lead-acid battery increases the performance of the battery. Leng, et al. manufactured a thermoset composite with conductive fillers and short fibers. Experimental results show that by adding 5 wt % nano-carbon particles and 2 wt % carbon short fibers 0.431 Ω-cm volume resistivity is obtainable. Yang, et al. manufactured a polyurethane thermoplastic composite with 5 wt % nano-tube carbon and measured 103 Ω-cm volume resistivity. Cho, et al. manufactured a polyurethane composite with 30 wt % carbon black that its volume resistivity is in a range of 1-10 Ω-cm. Paik, et al. tested a polyurethane composite with 8 wt % nano-tube that its volume resistivity is about 0.4×103 Ω-cm. Farshidfar, et al. investigate volume resistivity of HDPE and EPDM with 70-30 mixing ratio and different percent of carbon black. By increasing carbon short fibers as filler, mechanical and electrical properties are increased.
Conductive materials in the prior art can not offer combined characteristics namely, low weight, high strength, high stiffness, chemically corrosive resistivity and electrically conductivity. Thus, there is a need for an invention of a new polymeric composite to be able to offer all aforementioned characteristics.